System for distilling decomposable liquids



B. oRMoNT 2,505,571

sysma Fox DISTILLING- nEcomPosABm mquxns Filed Feb. 25. 1948 atented im25 1950 SYSTEM FOR DISTILLING DECOMPOSABLE LIQUIDS Bernard Ormont. NewYork, N. Y., assigner to Arthur W. Drake, Short Hills, N. J.

Application February 25, 1948. Serial No. 10,676 In France February 20,1946 Section l, Public Law 690, August 8, 1946 Patent expires February20, i966 5 Claims. l

This invention relates to a process of and apparatus for theVaporization and distillation of liquids in a single phase attemperatures Well below their atmospheric boiling points and withoutthe` use of special mechanical equipment for the production of vacuum.The present art and practice used for vaporization of liquids, Withatmospheric boiling points above the cracking or decomposing temperatureof said liquids, entails the use of steam and heat in vacuum, the vacuumbeing established by the use of mechanical equipment designed for thatpurpose, but this method is not only costly to install but is hazardousin operation and requires highly skilled workers in order to operate thesystem.

This invention, described below and set forth in detail, provides for aprocess for the use of high vacuum distillation in the presence of gasesand heat, which process is more eicient, less costly, more flexible, andmuch safer, than any operation heretofore proposed, and embodies all theadvantages of high vacuum distillation and also molecular vaporizationwithout the necessity oi employing expensive equipment with theaccompanying costs, hazards and disadvantages. With this in View, thepresent invention resides in the novel details of construction andcombinations oi parts constituting the apparatus, as well as in thenovel steps and combinations of steps constituting the process, all aswill more iully appear hereinafter and be particularly covered by theclaims.

Referring to the accompanying drawings forming a part of thisspecification and in which like numerals designate like parts in all theviews, s

Fig. 1 is a diagrammatic illustration partly in section and partly inelevation illustrating one form of apparatus for vaporizing the liquid;and

Fig. 2 is a diagram of a system in which the vaporizer of Fig. 1 isincorporated.

This process and invention is based on welllmown and well-recognizedphysical laws, among which is that which statesthat the molecular weightin pounds of any substance, when vaporized, Will occupy a Space of 359cu. ft. For instance, if we take a liquid or substance of a molecularWeight of 20 (such as liquid A for example in the followingdescription), then 20 lbs. of this particular liquid or substance whenvaporized will occupy 359 cu. it., or 1 lb. will occupy very close to 18cu. ft. 1f we take another substance of av molecular weight of 180 (suchas liquid B for example in the following description), the molecularweight in pounds would then be 180, and when vaporized would occupy asimi;

lar space of 359 cu. ft.. or 1 lb. would occupy very close to 2 cu. ft.So it will be seen that the ratio of the expansion of these twosubstances when vaporized is 10 to 1. i

With reference to Fig. 1, wherein there is illustrated one form ofapparatus for carrying out this invention, the liquid of low molecularweight is identified by the letter A and the liquid of high molecularweight is identified by the letter B. There is provided a pipe C intoone end of which extend two smaller pipes D and E through a suitableclosure member. The open end of pipe E is relatively close to theclosure member, but pipe D extends well beyond the end oi pipe E andapproximately to the farther end of pipe C,

`the end of pipe D also being open. Heat is applied externally to pipe Cand the vapors gen- `e-rated therein escape at F. The liquid (A.) ci

low molecular weight will pass from the open end of pipe E on to theinner surface of pipe C and be heated thereby. The small open circlesrepresent the molecules of liquid A as they flow in the direction of thearrow along the bottom oi pipe C, said molecules becoming hotter andhotter until linally they vaporize as at point or area G. We will assumethat the temperature at Gr is 300 F. and that liquid A has a molecularWeight of 20 and is completely vaporized at this point, the vaporspassing through the remainder ci pipe C and escaping at F.

Let us consider what is happening at point G. In l gallon there are 231cu. in. and, assuming atmospheric pressure to be present in pipe C, thepressure will be 760 millimeters. We will assume that one gallon ofliquid A weighs 8 lbs. lt was pointed out above that one pound of liquidA upon vaporization occupies 18 cu. ft. If we di-u vide 231 cu. in. by 8We find that l 1b, of liquid A occupies close to 29 cu. in., but thesame pound of liquid A when vaporized occupies 18 cu. it. or 31,104 cu.in. Hence there is an expansion in volume of liquid A, in going from theliquid to the vapor state, of close to 1,000 times its original volume.Considering one molecule of liquid A, at 760 millimeters pressure, beingconverted into a vapor at 300 F., it will be seen that the volumeoriginally occupied by the liquid molecule is increased l,000 times, orstated in other words the pressure in the original molecular volume isreduced to .76 millimeter. This is graphically indicated in Fig. 1 bythe dot-and-dash circle within pipe C at area G.

We will now consider liquid B of which, as pointed out above, one poundwhen vaporized occupies 2 cu. it. and whose characteristics are that ithas a boiling point of 900 F., a cracking point of 600 F., and that itvaporizes completely at 300 F. in a vacuum of l1 millimeters. Liquid Bis conveyed through pipe D inside of pipe C, thereby being'preheatedduring said conveyance, and then said liquid passes through the open endof pipe D and on to the inner surface of pipe C, ilowing along saidsurface in the direction of the arrow toward point or area G. Moleculesof liquid B are represented by the series of filled-in or solid circles.Upon reaching area G this liquid will have been heated to 300 F.

As the molecules of liquid B enter the molecular vacuumcreated at area Gby the vaporization of liquid A under the pressure system of .76millimeter and temperature of 300 F., said molecules cannot exist in theliquid phase, and hence they immediately and completely vaporize; theprocess is continuous as successive molecules (solid circles) of liquidB reach and enter the molecular vacuum created by the continuousopposite flow and vaporization of liquid A at area G.

In this system, contrary to ordinary distillation the fractionationdepends not only upon the relation between the vapor pressure of theliquids involved but also upon the differences of their molecularweights. Under a high vacuum the intra molecular spaces are greatlyincreased and thus offer an open path for molecules to pass betweenmolecules and thus prevent collision which might result in acondensation. This molecular eiect in vacuum on vaporization of liquidsis maintained in equilibrium not only by the continuous interilow oi'liquids of high molecular weight into vacuum molecular volumes inducedby the vaporization of the low-molecular-weight liquid, but also by thefact that the escape of molecules from the liquid to the vapor phase ismuch less than the rate at which the molecules in the liquid phasearrive at the surface of the liquid for vaporization.

As an example, let us take the vaporization of a fuel oil of a molecularweight of 200 by a liquid such as methanol having a molecular weight of32. Methanol has a boiling point oi' 147 F.; 32 lbs. of methanol willoccupy 359 cu. ft., wherefore 1 lb. will occupy 11.2 cu. it. or 19,353cu. in. As the gravity of methanol is 47.1 A. P. I., 1 gallon willweight 6.596 lbs.; therefore 1 lb. of liquid methanol will occupy 35 cu.in., or the expansion oi' liquid volume to vapor volume is 553 times.Therefore the pressure in the molecular volume of liquid methanol willbe reduced to very close to` 1.4 millimeters. The liquid fuel oilmolecules entering area G, and preheated to a temperature of 450 F.,cannot remain in liquid phase under a pressure of 1.4 millimeters, hencethey immediately proceed to vaporize as explained above, concomitantlywith the vaporization of the methanol molecules.

In the actual operation or commercial application of this new process,we can examine Fig. 2 wherein I is a pipe still, heated externally, inwhich leg 5 is connected with lower leg 4 by means of a connection 3.The high-molecular- Weight liquid enters leg l through pipe 2, and thelow-molecular-weight liquid (which is to be used as a means forvaporization) enters leg 4 through pipe I, and the vapors oi' bothliquids escape from still I5 to pipe 'I which is connected to reactionchamber I 0, which chamber is connected with gas heater B through pipeconnecion 8.

One or more inert gases enter gas heater 6 through connection 9 and areheated to a temperature higher than the temperature of the vaporsentering I0 through still connection l. The vapors from the stillcommingle and mix intimately with the heated inert gases in the reactionchamber I0. The products of the reaction escape from the upper portionof chamber I0 through connection II and can be subjected to furthertreatment as desired. Any portion of the vapors entering chamber IIIthrough connection I and which are not reacted in said chamber, escapefrom the bottom of chamber I0 throughconnection I2 where they can eitherbe led to storage through connection I 4 or passed back into still I5through connection I3 and pipe 2 for further or additional heating.

In operation, still I5 is heated to the proper temperature and then thelow-molecular-weight liquid, ilowing through I, enters the near end ofleg 4 and vaporizes therein. The area of molecular vacuum having beenestablished by said vaporization in leg-4 at approximately its midpoint,and the entire system having been heated to operating temperatures, thehigh-molecularweight liquid to be vaporized is introduced into leg 4through pipe 2 and escapes from the open end of said pipe at the fartherend oi leg I. whereupon said liquid ilows back to said molecular volumearea Where it is vaporized concomitantly with the low-molecular-weightliquid.

It is essential that the high-molecular-weight liquid be heated abovethe boiling point of the low-molecular-weight liquid, but to atemperature which is lower than the cracking point of any of the liquidconstituentsof said highmolecular-weight liquid. Inert gases arepreheated in still 6 to temperatures above that of any of the vaporsissuing from still I5. When the vapors from the still meet the heatedinert gases in chamber I0, a reaction takes place resulting in theproduction, in the vapor state, oi' products different from thoseoriginally existing in the high and low molecular weight liquids. Theseproducts, together with the inert gases, escape from chamber I0 throughconnection II, and thereafter all inert gases may be separated from saidreaction products and recycled back through connection 9 to be preheatedagain in i for reintroduction into chamber I0 for reuse in reacting uponvapors entering chamber I0 from still I5.

The controlling factor in the application oi.' this new process, andinvention, is that there shall be two liquids, the difference in themolecular weights of which shall be appreciable. The liquid having thehigher molecular weight (the one to be vaporized and distilled) ispreheated to a critical temperature while passing along a substantiallyhorizontal plane in one direction through the channel established bytube C, or the area occupied by the liquid having the lower molecularweight, and then the molecules of this higher-molecular-weight liquidare caused to flow in the opposite direction in said established channeland along substantially the same horizontal plane into the highmolecular vacuum area produced by the vaporization of the liquid of lowmolecular weight at said critical temperature. The character of theliquid to be vaporized, and the products desired to be obtainedtherefrom, are also controlling factors in the selection of thevaporizing-liquid having the lower molecular weight. For instance, highboiling petroleum oils, vegetable oils, or animal oils,can be completelyvaporized in the above manner by means of the vaporization of acetone,methanol, or any;

other liquid havingv a molecular weight which is appreciably lower thanthe molecular weight of the liquid to be vaporized. In some cases whereimmiscibility is required, it will be necessary to choose alow-molecular-weight vliquid for the vaporizing medium which will not besoluble in the condensates later produced from the vapors of thehigh-molecular-weight liquid. In other cases where miscibility isdesired, such solubility may take place. The ratio or proportion in thefeeding to the still of the two liquids, will closely approach the ratioof their molecular weights. and the liquid of low molecular weightpreferably should have the lowest heat of vaporization possible in theinterest of economy in conducting the process. It will .beunderstoodthat after the complete vaporizationof both liquids has takenplace at the reduced pressure area G, the combined vapors are lead fromsaid area through the ilue F to any suitable point for cracking and/orfractionation as well as condensation, or any other purpose as desired.Whereas in the foregoing the cracking has been referred to, in theinterest of simplicity, as heating the vapors with an inert gas, it isintended that other gases, vapors, means, apparatus, methods,procedures, instrumentalities and/or iniluences are contemplated and maybe used as substitutive of the specific inert gas and equipmentdisclosed herein.

It is obvious that those skilled in the art may vary the details ofconstruction and arrangements of parts constituting the apparatus, aswell as vary the steps and combinations of steps constituting theprocess without departing from the spirit oi this invention, whereforeit is desired not to be limited to the exact foregoing disclosure exceptas may be required by the claims.

What is claimed is:

l. The method of completely vaporizing a liquid, which comprises flowinga body of a different liquid in a layer in one direction along asubstantially horizontal plane in an established channel, said differentliquid having a molecular weight which is less than that of the liquidto be vaporized; heating the iiowing layer of the diiferentv liquid toboil the same. said heating being conducted at a pressure aboveatmospheric; conducting as a stream in the established channel theliquid to be vaporized in the same direction as but beyond the flowingand boiling layer of the diierent liquid; pre-heating said conductedstream by the same source of heat utilized Afor boiling said differentliquid; flowing the preheated stream of the liquid to be vaporized in alayer in the opposite direction along substantially the same horizontalplane in the established channel towards the layer of the differentliquid; heating the owing layer of the liquid to be vaporized to atemperature which is below that of the decomposing point of any of itscomponents but which is above the boiling point of said differentliquid; contacting in the established channel the layer oi' the heatedliquid to be vaporized with the layer of the boiling different liquid;maintaining a xed ratio of feed between the quantities of the twoliquids; maintaining a free vapor space above the owing liquid layers;and removing vapors from the vapor space.

2. The method of completely vaporizing a liquid,

which comprises flowing a body of a different i i different liquid tcboil the same, said heating being conducted at a pressure aboveatmospheric; conducting as a stream in the established channel theliquid to bevaporized in the same direc- `tion as but out of contactwith and beyond the flowing and boiling layer of the diilerent liquid;pre-heating said conducted stream by the same .source of heat utilizedfor boiling said different liquid; flowing the pre-heated stream lof theliquid to be vaporized in a layer in the opposite direction alongsubstantially the same horizontal plane in the established channeltowards the layer of the different liquid; heating the owinglayer of theliquid to be vaporized to a temperature which is below that of thedecomposing point of any of its components but which is above theboiling point of said diilerent liquid; contacting in the establishedchannel the layer of the heated liquid to be vaporized with the layer ofthe boiling different liquid; maintaining a fixed ratio of feed betweenthe quantities of the two liquids; maintaining a free vapor space abovethe flowing liquid layers; and removing vapors from the vapor space.

3. The method of completely vaporizing a liquid which comprises flowinga body of a different liquid in a layer in one direction along asubstantially horizontal plane in an established channel, said differentliquid having :a molecular weight which is less than that of the liquidto be vaporized; heating the flowing layer of the different liquid toboil the same, said heating being conducted at a pressure aboveatmospheric; conducting as a stream in the established channel theliquid to be vaporized in the same direction as but over, out of contactwith, and beyond the owing and boiling layer of the different liquid.pre-heating said conducted stream by the same source of heat utilizedfor boiling said diierent liquid. flowing the preheated stream of theliquid to be vaporized in a layer in the opposite direction alongsubstantially the same horizontal plane in the established channeltowards the layer of the different liquid; heating the flowing layer ofthe liquid to be vaporized to a temperature which is below that of thedecomposing point of any of its components but which is above theboiling point of said different liquid; contacting in the establishedchannel the layer of the heated liquid to be vaporized with the layer ofthe boiling different liquid; maintaining a iixed ratio of feed betweenthe quantities of the two liquids; maintaining a i'ree vapor space abovethe flowing liquid layers; and removing vapors from the vapor space.

4. A still for completely vaporizlng a liquid, comprising means forflowing a body of a different liquid in a layer in one direction along asubstantially horizontal plane in an established channel, the differentliquid having a molecular weight which is less than that of the liquidto be vaporized: means for heating the owing layer of the differentliquid to boil the same: means for conducting a stream of the liquid tobe vaporized in the same direction as but to a point beyond the flowingand boiling layer of the different liquid, said conducting means beingso located that its contained stream will be substantially in the sameestablished channel and will be preheated by the heat oi said heatingmeans, said conducting means adapted to direct its preheated stream intothe same substantially hori'fontal plane for flowing as a layer in theopposite direction towards and contacting .the boiling layer of thedinerent liquid; said means for heating including adof relatively largediameter, a pair of liquid conducting pipes entering said tube adjacentone of its ends, said rpair of pipes being each of relatively smallerdiameter, one of said pipes for conducting the liquid to be vaporized,the other pipe for conducting a different liquid having a molecularweight which is less than that of the liquid to be vaporized, the endsof said pipes in said tube being open and directed for discharging theircontained liquids directly againsty an inner surface of said tube, thepipe for the different liquid terminating closely adjacent its entryinto said tube, the pipe for the liquid to be vaporized extending insaid tube well beyond the end of its companion pipe, means for heatingsaid tube and its liquid contents, and a vent at the other end of saidtube for the discharge of the valpors created in said tube.

` BERNARD ORMONT.

REFERENCES CITED The following references are of record in the file ofthis patent:

. 8 UNITED STATES PATENTS Number Name Date 444,202 Mason Jan. 6, 18911,135,506 Dubbs Apr. 13, 1915 1,538,265 Arnold May 19, 1925 1,622,126Wecker Mar. 22, 1927 1,751,182 Wilson Mar. 18, 1930 1,758,590 Wilson1---- May 13, 1930 1,734,561 Watts et a1. Dec. 9, 1930 1,851,093Gensecke Mar. 29, 1932 1,871,051 Franzen Aug. 9, 1932 1,924,919 FlowersAug. 29, 1933 2,316,670 Colgate Apr. 13, 1943 2,368,669 Lee et al. Feb.6, 1945 2,396,600 Pacevitz Mar. 12. 1946 2,420,234 Filachione May 6,1947 FOREIGN PATENTS Number Country Date 235,792 Great Britain June 19,1923 327,166 Great Britain Mar. 31, 1930 876,585 France Nov. 4, 1941OTHER REFERENCES Morton, Laboratory Technique in Organic Chemistry,McGraw Hill, 1938, pages 143, 144.

Badger and McCabe, Elements of Chemical Engineering," McGraw Hill, 2nded., 1936, pages 644, 645.

Othmer, Partial Pressure Processes, Ind. and Eng. Chem. (1941), vol. 33,pages 1106-1112.

Keyes, Binary Liquid Mixtures. Ind. and Eng.

Chem. (1941), vol., 33, pages 1019-1021.

